﻿using System;

using System.Collections.Generic;



class PrimeFactorization

{

    static void Main()

    {

        Console.Write("请输入一个正整数：");

        if (int.TryParse(Console.ReadLine(), out int n) && n > 0)

        {

            Console.WriteLine(GetPrimeFactors(n));

        }

        else

        {

            Console.WriteLine("输入无效！");

        }

    }



    static string GetPrimeFactors(int n)

    {

        if (n == 1) return "1 = 1";



        int original = n;

        List<int> factors = new List<int>();



        for (int i = 2; i <= n; i++)

        {

            while (n % i == 0)

            {

                factors.Add(i);

                n /= i;

            }

        }



        return $"{original} = {string.Join(" * ", factors)}";

    }

}